Helicobacter pylori is a highly motile, spiral-shaped, Gram-negative bacillus surrounded by flagella. It was first isolated in 1983 by Robin Warren and Barry Marshall, who linked it to the development of gastric ulcers, a discovery for which they were awarded the Nobel Prize for Medicine in 1995.

In infected persons, Helicobacter lives in the mucous layer of the stomach where, thanks to its enzyme urease, it produces ammonia and partially neutralizes the natural acid pH of the stomach, protecting itself from this, allowing it to survive and proliferate. The bacterium also secretes certain proteins that attract macrophages and neutrophils, producing inflammation in the affected area, i.e. gastritis.

Epidemiology

Helicobacter pylori infection is very common and usually occurs in childhood, via the fecal-oral or oral-oral route. The prevalence of Helicobacter pylori varies between and within population groups. The lifetime risk of infection in people in developed countries is between 40% and 60%, reaching 90% in developing countries, where approximately 50% of the population is already infected by the age of 10 years. However, only 10-25% of those infected develop symptoms.

Pathologies and complications

Helicobacter pylori has been associated with different diseases, most of them of the digestive tract. Its involvement in chronic active gastritis, its association with gastroduodenal ulcer and its inclusion by the IARC among type 1 carcinogens has made it one of the microorganisms of greatest interest in human pathology.

Helicobacter can cause complications such as:

  • Chronic gastritis: the most frequent inflammatory process in humans and closely related to pylori infection.
  • Duodenal ulcer and gastric ulcer: perforations of the mucosa of the intestine or stomach, respectively.
  • MALT lymphoma: it is a lymphoma that predominates in adulthood, is more frequent in women and constitutes 5-10% of gastric neoplasms.
  • Non-ulcer dyspepsia: chronic recurrent pain or discomfort in the upper abdomen.
  • Gastric cancer: pylori infection is considered a risk factor in the development of stomach cancer.

Symptoms

  • Burning sensation or heartburn in the upper abdomen, below the sternum.
  • Stomach pain.
  • Strain.
  • Premature satiety.
  • Lack of appetite.
  • Nausea and vomiting.
  • Darkening of the stool, which may become black.
  • Anemia and fatigue.

Do you have any of these symptoms? Don't let it go, gastric discomfort is not normal. Consult your doctor.

Diagnosis

For the diagnosis of Helicobacter pylori, there are different techniques:

  • 13C-labeled urea breath test: is a non-invasive test that consists of taking a tablet of labeled urea. In the presence of pylori, its urease activity degrades urea releasing 13C-labeledammonia andCO2, which is detected in the exhaled air sample. Moreover, the test is much more reliable and sensitive if a citric acid drink is administered beforehand. This avoids the occurrence of false negatives.
  • Stool antigen determination: consists of the collection of a stool sample and its examination for the presence of pyloric antigen using a diagnostic method called ELISA with monoclonal antibodies. When the antibodies used are polyclonal, the reliability of the test is reduced and false positives are common.
  • Serological test: consists of the extraction of a blood sample and its analysis to detect antibodies against pylori . It is only used when there is a gastric pathology, such as bleeding, atrophic gastritis or certain tumors, which may alter the interpretation of previous tests.
  • Digestive endoscopy: allows the collection of a biopsy of the gastric mucosa and its histological analysis to detect urease activity or to microscopically identify the presence of the bacteria. However, it is an invasive technique and its sensitivity is not very high, since the tissue sample may not contain the bacteria.

Treatment

Your physician will determine the treatment based on the patient's characteristics. However, the goal is always to eradicate the bacteria, so the treatment is usually antibiotic therapy. However, H. pylori has developed resistance to several antibiotics, so sometimes it is not 100% eliminated and it is necessary to repeat the treatment with a different antibiotic therapy.

It is important to perform a diagnostic test again after treatment to confirm the eradication of Helicobacter pylori. Ask your doctor for it.

Bibliography

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